Alter config format to lists of dictionaries

Rather than the previous dictionary of lists.

Change-Id: I0f8ffba15da489da097b14388699685f22b0579f
diff --git a/tests/fixtures/config/in-repo/main.yaml b/tests/fixtures/config/in-repo/main.yaml
index df7dadd..e8b7665 100644
--- a/tests/fixtures/config/in-repo/main.yaml
+++ b/tests/fixtures/config/in-repo/main.yaml
@@ -1,5 +1,5 @@
-tenants:
-  - name: tenant-one
+- tenant:
+    name: tenant-one
     include:
       - common.yaml
     source: